That metaphor implies there is a rigid barrier that blocks women from the top echelons of power, explains Eagly, the Northwestern University psychology department chair known for her research on the psychology of gender.

But with 23 percent of American CEOs of organizations now women, according to the U.S. Bureau of Labor Statistics, that's clearly not what's happening today.

A more accurate metaphor for the obstacles women encounter is a labyrinth- "a series of complexities, detours, dead ends and unusual paths," says Eagly. This labyrinth includes sex discrimination, women's domestic responsibilities and sometimes women's own failure to believe in themselves.

That theory is explained in a book due this fall, "Through the Labyrinth: The Truth about How Women Become Leaders" (Harvard Business School Press), co-written by Eagly and Wellesley College psychology professor Linda Carli, PhD.

Eagly and Carli amassed the research on women's leadership from psychology, economics, communications, management and sociology. Their findings document the hurdles women leaders face and suggest ways they can negotiate them.

"The motivation for the book is to help both men and women understand the dilemma women are placed in," says Carli.

To increase gender equality in the workplace, the authors surmise, change must take place on four levels: the culture, the organization, the family and the individual.

Conflicting expectations

Though discrimination is generally less blatant today, women are still treated unfairly, often due to prejudice and stereotypical thinking, say the authors. "The stereotype of men is more similar to the stereotype of leaders," explains Eagly. As a result, women may not be seen as "tough enough" or having "what it takes" to perform at the top levels.

When women are in leading roles, people expect them to have the qualities of both leaders and women, but that can require a complex balancing act. If they are too tough, women can be disparaged for being "just like a man," says Eagly. If they take a softer approach, they can be viewed as weak or incompetent.

A case in point is Hillary Clinton. She's skilled, confident, knows politics, but people criticize her for not being warm enough. "People rarely have that expectation for a man," points out Eagly. "Do we worry about John McCain being warm?"

To walk that fine line to leadership, the authors suggest that women blend the characteristic male qualities, such as decisiveness and toughness, with the female qualities of warmth and inclusiveness. In short, a successful woman leader generally shows signs of femininity, while assertively taking charge and demonstrating her competence. She can show her proficiency, for example, by being well-prepared and mastering her job responsibilities. She can reveal her femininity by warmly supporting her colleagues.

Women must also build their social networks to be successful leaders, say the authors. Ironically, even though women are viewed as more social beings, they often have less "social capital" in organizations than men.

"There are always these networks within organizations in which decision-making occurs in informal contexts and women commonly get excluded from them-for example, the guys who play basketball on Friday nights," says Eagly.

And those networks are essential, not only in providing emotional support, but in helping to make deals and ferret out the inside scoop on organizational problems, emerging projects or promotions.

That doesn't mean women need to barge in on the Friday night game, Eagly says. They might instead invite colleagues for coffee or an activity or event of their choice.

"Women have to be assertive, not wait for an invitation and sometimes bend to masculine culture," Eagly advises.

Family ties

These days, a fast-track career demands long hours that often stretch into evenings and weekends. Since women typically have more domestic responsibilities than men, they are usually the ones to cut back their work hours or abandon their jobs when a couple decides to have children.

"These types of detours make it more difficult for women to reach a position of greater responsibility and power," says Eagly. "It's a major complexity in women's lives that men don't face to as great a degree, typically."

Eagly and Carli fear that many women drop out of employment not fully understanding the costs. Not only is it harder for them to rejoin the work force later, but extensive research suggests that a woman's physical and mental health are better if she has multiple life roles-usually both family and employment.

While emphasizing that there is "no one way" to balance work and family, the authors acknowledge that combining child care and employment makes for a very demanding period of life, yet women should consider sticking with both anyway. "In the long run, women who have multiple roles have greater life satisfaction and greater health, despite the complexity of it," Eagly says.

One of the most interesting findings for the book, says Carli, is research that shows today's employed mother spends as much time on child care as the non-employed mother of 1975. "There's all this pressure on women for being 'bad mothers' for working and not spending enough time with their children," says Carli. "And guess what? They are spending a lot of time with their children and sacrificing personal time to do it."

The authors note another emerging phenomenon: Today's fathers are increasingly involved in child care and worry that they are not doing enough.

"Men are not really doing a huge amount of housework, but they are embracing the child care and are still doing their long hours at work," says Carli.

Self-improvement

New data show that today's women are better educated than ever before, and now surpass men in educational achievement. But even with those gains, says Carli, some women doubt their worth in the workplace.

"They feel they don't deserve success or think, 'I should be happy with what I have,'" she notes. And, because women tend to compare themselves with other women-rather than men-they don't often push for the higher salaries and better job perks that men enjoy.

"More often, women need to think about how men are doing," says Carli. They should measure themselves against men with the same qualifications and gather as much data as they can about typical salary and benefit packages for their line of work, the authors advise.

Women also undermine themselves by not talking up their accomplishments, say the authors. According to the research, that may be because women who tout their successes are seen as lacking "feminine niceness" and their immodesty is frowned upon.

"Women need to be tempered in their entitlement and self-promotion, a challenge men don't even need to think about," says Carli.

To avoid disapproval, a woman can promote herself in more subtle ways, say the authors, by asking others to react to her clearly superior ideas, or, when she is being praised, modestly thanking those who helped her.

It's a tall order, say Eagly and Carli, but it shouldn't all be on women's shoulders.

"Women can't be expected to tear down the labyrinth on their own," says Carli. "Organizations have to reduce barriers that favor men over women, men have to share more fully in domestic responsibilities, and society in general has to have a more open and inclusive understanding of what a good leader is."